246 MARSHALL : ADDITIONS TO 'BRITISH CONCHOLOGY.' 



Jeffreys also records a valve from Shetland and another 

 from the Orkneys (' B. C.,'vol. ii., p. 180). It was also taken 

 in the 'Porcupine' and. other expeditions off the coast of 

 Ireland, Shetlands, and North of Hebrides. 



Montacuta donacina S. Wood. There is no doubt of this 

 species living in our seas, but for some unaccountable 

 reason it appears difficult to get at. As long ago as 1839 

 Jeffreys found a valve at Falmouth, then another in the 

 Shetlands in 1868, and I found a third in Torbay in 1890. 

 The latter valve is as perfect and fresh as if only just 

 vacated by the animal. I should not be surprised if it 

 proved to be a parasitic species. References to it will be 

 found in ' B. C.,' vol. ii., p. 216; vol. v., p. 178, and it is 

 figured in the Supplementary Plates. A valve was taken 

 in the ' Porcupine ' cruise at Lough Swilly, and M. Joly 

 has obtained a living specimen off Algiers. 



M. bidentata var. triangularis. Jeffreys makes reference 

 to this variety in some of his lists, but I do not think he 

 has described it. It is triangular instead of ihomboidal, 

 and I have it from Torbay, Milford Haven, Skye, Aber- 

 deen, Dornoch Frith, Shetland ; also from Drobak, Nor- 

 way, 60 — 100 fathoms. 



Cypricardia litFiopiiagella Lam. See 'B.C.,' vol. ii., 

 p. 263 ; vol. v., p. 180, and figure in Supplementary Plates. 



Cardium aculeatum var. depressa Marsh. Shell de- 

 pressed, and expanding at the sides. Occasionally found 

 with the type in South Devon. 



C. tuberculatum var. suborbicula Marsh. This variety 

 is also depressed, and has a rounded instead of an oblique 

 outline. Found with the last. Probably these two 

 varieties are generally diffused with the types. I have 

 named them so that they may take a corresponding 

 position to similar varieties of most other species of Car- 

 dium, as I think they deserve. 



J.C, viL, Oct. 1893. 



